CDS. Unit Gross Pollutant Traps WATER QUALITY TECHNOLOGIES

Transcription

1 CDS Unit Gross Pollutant Traps WATER QUALITY TECHNOLOGIES

2 The leading stormwater pollutant trap Characteristics of the CDS Unit Non-blocking functionality 95% capture of gross pollutants >1mm 95% sediment capture >200µm Captures organics and oils Captures adsorbed toxics and nutrients Can treat any pipe or multiple pipes Various sump sizes available Customised bypass requirements Underground - small footprint Easy installation No moving parts Lowest life cycle costs More water treated than comparable treatment designs Pollutants stored in the sump, not the screens Applications Subdivisions and roads Residential, commercial and industrial developments Carparks and shopping centres Pre-treatment for wetlands Pre-treatment for reuse applications Pipes, channels, culverts and creeks Other CDS models are available for nonstormwater applications involving high flow solids/liquids separation, such as industrial processes and sewer overflows. High performance GPTs using patented CDS indirect screening technology

3 Selecting a CDS Unit The size and type of CDS GPT required depends on catchment area, flows, pollution loads, performance requirements, maintenance method, hydraulic limitations and site constraints. Visit the Rocla website ( or solutions@rocla.com.au for a sizing request. Details submitted with this form provide all the information needed to calculate the size of device most applicable for the site. CDS Unit Models CDS Construction Catchment Unit No Material Area (ha) CDS0506 in-line polymer < 1 ha CDS0708 in-line concrete < 2 ha CDS0708M in-line concrete < 4 ha CDS1009 pre-cast concrete 2-8 ha CDS1012 pre-cast concrete 4-12 ha CDS1015 pre-cast concrete 6-15 ha CDS1512 pre-cast concrete 8-20 ha CDS2018 pre-cast concrete ha CDS2028 pre-cast concrete ha CDS3018 pre-cast concrete ha CDS3024 pre-cast concrete ha CDS3030 pre-cast concrete ha How Stormwater Pollutant Traps Rate The CDS GPT is rated the most effective stormwater pollution trap in every independent comparison. On-Line Devices POOR Off-Line Devices GOOD Off-Line Non-Blocking Devices BETTER Off-Line Non-Blocking Devices with Double Off-Line Storage (CDS) BEST Independent studies show that no GPT rates higher than the CDS GPT on performance and pollution retention. Complete design service Rocla offers a complete design service for CDS products that takes into account the catchment s characteristics, pollution load, hydraulic site constraints and opportunities, system capacities, velocity, backwater, as well as the location of services and access for cleaning. Hydraulic reports are available on request and are automatically carried out for larger units. Diversion chamber Precast diversion chambers can be manufactured to suit most typical installations, or chambers can be tailored to meet the hydraulic limitations of the site. The diversion chamber has the capacity to cater for the highest possible flow in the stormwater system. The chamber is configured on the assumption that the CDS unit has not been maintained and there is no flow passing through the unit. A weir is located within the diversion chamber to create a driving head and direct the majority of flows into the CDS GPT. Diversion chamber options Precast diversion chambers Semi-precast diversion chambers Customised designs for multiple pipes, drops and bends In-situ channel designs Fixed or collapsible weirs Any flow capacity No flooding The CDS GPT and diversion chamber design depends on the system capacity and site constraints. Rocla will design the most suitable CDS GPT configuration to meet project requirements. Maintaining CDS GPTs CDS units have the lowest life-cycle costs due to their non-blocking functionality, large off-line storage and multiple cleaning options. There are 3 methods of emptying CDS GPTs: Removable basket Material grab Suction method With no requirement to unblock screens, confined space entry is minimised. Large off-line sump volumes (up to 10m 3 available) also minimise cleaning frequency, reducing maintenance costs and hence life-cycle costs over the next 50 years.

4 Off-line CDS Unit Operating Principle Compact in-line GPTs for smaller catchments Weir Diversion chamber Plan CDS GPT Lid Access shaft CDS 0506 Diversion chamber Weir Continuous deflection screen Front elevation Off-line storage sump CDS 0708 Optional oil baffle Side elevation CDS 0708 Maxi

5 Patented screening technology CDS gross pollutant traps (GPTs) are designed to capture and retain gross pollutants, litter, grit, sediments and associated oils, utilising patented CDS indirect screening technology. Continuous deflective separation (CDS) The CDS Unit comprises a GPT located next to a diversion chamber Direct screening Indirect screening (CDS) It has long been acknowledged that best management practice for stormwater pollutant traps involves locating the devices off-line. GPTs located on-line suffer badly from turbulence and eddies, often resulting in the re-suspension and loss of previously captured pollutants. GPTs which store pollution in the screening area suffer decreasing screen area and therefore decreasing flow rates, as they fill up. GPTs which function by direct filtration have a treatable flow rate decay that is proportional to the percentage of screen blockage. GPTs that utilise a vortex only, without a screen, cannot guarantee neutrally buoyant pollution removal. Only CDS units combine the advantages of being off-line, having non-blocking functionality, vortex forces and storing pollution outside the screening area. For these reasons, no other device is equivalent to a CDS Unit. The only off-line GPT with non-blocking screens and storage outside the screening area

6 CDS Unit Gross Pollutant Traps For further information on CDS products and solutions Call Rocla on For an information kit Or visit our website Sydney Dapto Dubbo Newcastle Glen Innes Grafton Canberra Melbourne Avoca Traralgon Wodonga Brisbane Toowoomba Mackay Cairns Adelaide Perth TECHNOLOGIES Trade marks of Rocla Pty Limited ABN A member of the Fletcher Building Group Rocla Pty Limited November 2007 The content of this brochure is protected by copyright and may not be reproduced in any form without the prior written consent of Rocla Pty Limited. The information in this brochure is as far as possible accurate at the date of publication, however, before application in any situation, Rocla recommends that you obtain qualified expert advice confirming the suitability of product(s) and information in question for the application proposed. While Rocla accepts its legal obligations, be aware however that to the extent permitted by law, Rocla disclaims all liability (including liability for negligence) for all loss and damage resulting from the use of the information provided in this brochure. 5469